Chronic lymphocytic leukemia (CLL) patients display a different CD5 expression than some other blood cancers. Watch to learn about CD5 expression and how monitoring plays into CLL patient care.
The protein of CD5 is abnormally expressed (or displayed) in T cells and/or in B-1a B cells in chronic lymphocytic leukemia (CLL) and is often referred to as a marker. The small CD5-positive B lymphocytes multiply and accumulate in a CLL patient’s blood, bone marrow, and secondary lymphoid tissues and then create the condition of CLL. Though some blood cancers show as CD5-negative status, CD5 is shown as overexpressed along with CD19 and CD23 combined with weak expression of CD20 and CD79b in CLL patients.
Recent research studies looking at different CD markers including CD5 show that monitoring of CD expression changes over time can help more accurately determine prognosis for CLL patients.
“So, there is kind of a code of these markers on the surface of all of your blood cells that can tell what type of cells they are. So, for CLL in particular, we’ll see that the cells express some of the normal markers we would see on a normal B lymphocyte.
Things like CD19, CD20, CD23. But they also express a marker called CD5, which is found on normal T lymphocytes but shouldn’t be found on B lymphocytes.
And so, this collection of surface markers can make the diagnosis of CLL. Sometimes, we do need to do extra studies like a bone marrow biopsy or a lymph node biopsy. But oftentimes, those are not necessary at the time of diagnosis.”
As always, check with your CLL specialist if you have more questions about CD5 expression in CLL.